A “FIT and healthy” man with no history of allergies died a day after being prescribed antibiotics for toothache.

Shop assistant Mark Johnson collapsed at work and was taken to hospital but suffered a heart attack and could not be revived.

The 36-year-old, from Hoylake, visited his dentist on July 2 last year complaining of pain in his upper jaw and was given amoxicillin – a form of penicillin – to ease the symptoms.

But he fell ill the following day while at work at Sainsbury’s in Prenton.

Today, after an inquest ruled he had died from natural causes, Doreen and Bill Johnson said: “We couldn’t have wished for a better son.”

Dr Waleed Askar, from the Arno Dental Practice in Prenton, told the hearing that Mr Johnson had been given the same antibiotic “numerous” times with no ill-effects.

Coroner’s officer Donald Johnston said Mr Johnson’s parents went to collect him after being told he was unwell.

He said: “When he started to walk out of the canteen he appeared to stiffen up and clench his teeth. He then turned blue and slid down the wall.

“Paramedics found his airway was partially obstructed.

“He was given oxygen and adrenalin at Arrowe Park Hospital, but had a cardiac arrest.”

A post mortem found some signs of heart disease but the main cause of death was anaphylaxis, a type of allergic reaction, caused by an allergy to penicillin.

In a statement, Dr Askar said: “Following the discussion of treatment options, as the tooth was unrestorable, he said he preferred to have the root removed under intravenous sedation at Arrowe Park Hospital rather than with local anaesthetic, as he was a very nervous patient.

“He did not have any known allergies and he had received prescriptions for amoxicillin on numerous occasions.”

Mr Johnson had learning difficulties and started at Sainsbury’s 10 years ago collecting trollies before being promoted to tills.

The Everton fan lived with his parents in Strand Road, Hoylake, but was saving up for a future with fiancee Kate. The couple met three years ago at a weekly event in Birkenhead for people with learning disabilities.

Recording a verdict that his death was due to natural causes, Wirral coroner Christopher Johnson said: “Mr Johnson was fit and healthy with no history of allergies. Dr Askar prescribed a course of amoxicillin which he had received previously but on this occasion, he collapsed.”

In a card to his parents after his death, managers and colleagues at Sainsbury’s praised Mr Johnson as a “fantastic colleague who had the ability to brighten the darkest, wettest days”.

Mum Doreen said: “He was just brilliant and everyone loved him. Mark didn’t just pass through – he made a difference to people’s lives.

Dad Bill said: “Mark was just a lovely lad. Every Friday he’d bring home a bunch of lillies for his mum and put out the bins for her and the neighbours. Nothing was too much trouble. He was never late to work and even if he wasn’t in Sainsbury’s he’d go and help out at the corner shop or at his sister’s pub.”